ESI, Estech Systems Inc., has been producing phone systems for years now. Producing both digital and IP based endpoints, their phone systems are as varied and powerful as their telephones. This is a brief introduction into some of their most popular phone systems.
ESI IVX Phone Systems:
The ESI IVX series of phone systems come in several classes, the C-Class, E-Class, and S-Class systems. In addition, there is a first and second generation versions of the IVX phone systems. These digital phone systems support several different connections. They can be connected through PRI, ISDN, or analog POTS trunks.
Of the IVX phone systems, the C-Class is the entry level variant. The C-Class can support up to 6 lines by 12 phones with an optional expander. The next step is the S-Class, perfect for slightly larger businesses, and the second generation version can support up to 16 lines and 32 phone extensions. The first generation IVX S-Class was 12 lines by 24 stations.
The largest of the IVX phone systems is the E-Class. The E-Class can handle up to 66 lines by 84 phone stations. The IVX E-Class is an enterprise level phone system. It includes a 140 hour voicemail capacity.
ESI Communication Servers:
The ESI Communication Servers are a hybrid phone system, both digital and IP based. The communication servers are perfect for those looking to stick with traditional digital systems, merge slowly over to an IP based solution, or run an entirely IP based system. These servers are much newer than the older IVX systems and include support for SIP.
The ESI Communication Servers range from the simple, small business oriented ESI 50 to the enterprise ready ESI 1000. The communication servers support both PRI and SIP trunks.